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DURF: what actually goes into the 10 per cent calculation

With ruling No 174 of 16 September 2026, the Revenue Agency has further expanded the scope of payments contributing to the 10 per cent threshold required for the issue of the DURF, the Italian single tax compliance certificate: it now includes withholding tax on bank interest income and, up to the amount of the tax credit available, taxes paid abroad. Here is how the fraction is calculated, what has been admitted since 2020, and what to do if the certificate is not issued.

A business working under a contract (appalto) obtains the DURF if it has been active for at least three years, is compliant with filing obligations, has no amounts assigned for collection above the statutory threshold, and has made, over the last three years, payments equal to at least 10 per cent of the declared revenue or fees. This percentage is not found in the financial statements: it is a fraction with its own rules, and for six years the Revenue Agency has been expanding its numerator one clarification at a time. Ruling No 174 of 16 September 2026 adds two items that no one would have included by reading the provision alone.

Who the rules apply to

Article 17-bis of Legislative Decree No 241 of 9 July 1997 — introduced by Article 4 of Decree-Law No 124 of 26 October 2019, converted by Law No 157 of 19 December 2019 — applies only to principals who are withholding agents under Article 23, paragraph 1, of Presidential Decree No 600 of 1973 and are resident for direct tax purposes in Italy: excluded, among others, are non-residents without a permanent establishment, condominiums, and non-commercial entities for their institutional activities only.

The provision requires these persons to obtain copies of the F24 payment forms for withholdings applied to workers employed in the works, but only if all the conditions of paragraph 1 are met simultaneously: works or services with a total annual value exceeding 200,000 euro, awarded through contracts, subcontracts, assignments to consortium members or “contractual relationships however designated”, with predominant use of labour, at the principal’s business premises and using capital assets owned by or attributable to the principal in any form.

The threshold refers to the calendar year and to each awardee company, summing all contracts in force during the year, new contracts with the same company, and subsequent amendments; however, for annual or multi-year contracts at a predetermined price, the full price is not summed, but only the portion attributable to the year on a pro rata temporis basis, calculated in full months, with a shift to the following month for contracts and amendments executed after the 15th day of the month. More importantly, the threshold is not tested at each link in the chain: to prevent an award above 200,000 euro from escaping the rules by splitting it into multiple smaller sub-awards, it is measured solely in the relationship between the original principal — even if this is a party outside the scope — and the awardee. Exceeding it there is a necessary but not sufficient condition: a subcontract of 150,000 euro within a contract of 450,000 euro is not below the threshold, but is only included if, in relation to that principal, there is also predominant use of labour at its premises and capital assets attributable to it.

Two clarifications often change the outcome. The classification given by the parties is not decisive in either direction: what matters is not the legal label, but the actual occurrence of the substantive conditions. Therefore, the supply of goods with installation may be included, while contracts for the supply of labour under Article 30 of Legislative Decree No 81 of 15 June 2015 are excluded; however, cases of illegal supply of labour are included, regardless of the form chosen. The scope has a clear downstream boundary: the awardee must be a business, so contracts for services under Article 2222 of the civil code entered into with self-employed professionals are excluded, while those concluded with companies that employ employees or equivalent personnel are included. Finally, the status of principal is relative: it may equally be held by the original principal, contractors, subcontractors, consortia, and consortium members, so that in a chain of subcontracts the same company is often both an awardee towards the party that commissioned the work and a principal towards its own subcontractors.

The contractual request is not the legal obligation

It often happens, as described by the applicant in the ruling request decided in September, that a company believing it operates outside the high-labour-intensity scope is still asked for the DURF because principals have adopted it as a standard contractual compliance safeguard. It should be noted that, in that context, the Agency assumed the facts as presented without verification and excluded from consideration any assessment of whether the requirements were met.

The two aspects must be kept separate. The contract does not extend the scope of Article 17-bis: if the conditions of paragraph 1 are not met, the principal is neither required to suspend payment under paragraph 3 nor liable for the sum under paragraph 4. However, the clause remains fully effective between the parties: under the freedom of contract recognised by Article 1322 of the civil code, the principal may make payment conditional on the delivery of the document, and the company that fails to produce it is liable under the contract, not under the law. It is therefore advisable to examine how the clause is structured — whether it imposes a genuine delivery obligation on the company, non-compliance with which opens the way to termination and contractual penalties, or whether it merely makes the consideration payable subject to delivery — and what it suspends and for how long. If the clause is contained in standard terms prepared by the principal, Article 1341, paragraph 2, of the civil code may require specific written approval, including for clauses that grant the drafter the power to suspend performance of the contract. Moreover, contractual suspension is not without limits: it must remain proportionate and consistent with good faith in performance, and in commercial transactions between businesses, Article 7 of Legislative Decree No 231 of 9 October 2002 renders void agreements on payment terms that are grossly unfair to the creditor.

What the certificate spares the business

Paragraph 5 exempts from those obligations businesses that notify the principal, attaching the relevant certification, that the requirements were met on the last day of the month preceding the deadline set by paragraph 2. Without that communication, withholdings must be paid using separate F24 forms for each principal and without the possibility of offsetting, and within five working days after the deadline, the F24 forms and a list naming the workers employed must be sent to the principal — and, where the company is a subcontractor, to the contractor as well, with their tax code, hours worked, related remuneration, and withholding details. This is the burden that the certificate eliminates.

The attested requirements are twofold. First: having been active for at least three years, being compliant with filing obligations, and having made, in the tax periods covered by the income tax returns filed in the last three years, payments recorded in the tax account not less than 10 per cent of the revenue or fees resulting from those returns. Second: not having amounts assigned for collection — entries on the tax roll, enforceable assessments, or INPS debit notices for income taxes, IRAP, withholdings, and social security contributions — exceeding 50,000 euro, due and unpaid in the absence of suspension, excluding amounts under non-lapsed instalment plans.

The certificate is valid for four months from issue and is made available, from the third working day of each month, by any territorial office of the competent Provincial Directorate based on the tax domicile; for large taxpayers, the Regional Directorates provide it. When the principal is a public authority, the requirements are certified by self-certification under Presidential Decree No 445 of 28 December 2000.

How the fraction is calculated

Circular No 1/E of 12 February 2020, at point 3.1, sets the two terms. The numerator includes “all payments made via the F24 form for taxes, contributions, and INAIL insurance premiums, gross of offset credits, during the tax periods covered by the income tax returns filed in the last three years”, explicitly excluding payments of debts registered for collection; the same circular already admits the “theoretical tax” corresponding to the company’s own total income under Article 121 of the TUIR attributed to the tax consolidation under Article 121 of the TUIR. The denominator consists of the total revenue or fees resulting from the declarations of the same three-year period. If, in the three-year period, the deadlines for only two declarations have expired — as in the case of a company established just over three years ago — the check is performed on two declarations.

What has been added to the numerator

The scope has been expanded gradually. With Resolution No 53/E of 22 September 2020, the following were included in the calculation: VAT settled by the principal under the reverse charge mechanism and VAT relating to split payment transactions, the theoretical tax on income attributed by transparency to partners, and the theoretical VAT resulting from the periodic settlement of the subsidiary, settled by the controlling entity in the group VAT settlement: in all these cases, the liability accrues to the business itself, while the payment is made by another related party.

With ruling No 63 of 3 March 2026, payments made via F24 to settle notices of irregularity and electronic notices issued following automated checks — Articles 36-bis of Presidential Decree No 600 of 1973 and 54-bis of Presidential Decree No 633 of 1972 — were admitted, as they demonstrate the willingness and ability to comply; the same ruling clarified that payments are allocated by reference to the date on which the payment was made, within the period from the start of the tax period of the earliest declaration to the end of that of the most recent declaration. The applicant had proposed to calculate them net of penalties and interest, but the Agency did not rule on this: it is prudent to keep the three components separate.

Ruling No 174 of 2026 now adds two further items. The first is the withholding tax on interest earned from current accounts and bank deposits, applied by credit institutions under Article 26, paragraphs 2 and 4, of Presidential Decree No 600 of 1973 and included in row RN15 of the Redditi SC form: the Agency admits them “specularly” to the cases in Resolution No 53/E, as they represent a levy economically attributable to the company, of which only the payment is made by the withholding agent. However, the opinion concerns only that specific case, not the entire content of the row.

The second concession is more delicate. Taxes paid abroad do not pass through the Italian tax account, and the question was precisely whether they should be excluded for this reason; the applicant had, however, argued the opposite, and the Agency accepted that argument: foreign taxes can be included up to the amount of the credit recognised under Article 165 of the TUIR (row RN13), because their use to offset the IRES due in Italy “in substance amounts to a means of paying the tax”.

From 1 January 2027, the provision is renumbered

It is worth noting this, as multi-year contracts will span the date. Article 17-bis is in force until 31 December 2026 and is repealed, with effect from 1 January 2027, by Article 241, paragraph 1, letter t), of the consolidated text on payments and collection, attached to Legislative Decree No 33 of 24 March 2025; the date, originally set one year earlier, was postponed by Article 4, paragraph 4, of Decree-Law No 200 of 31 December 2025. From that date, the same rules will be found in Article 7 of the consolidated text: the threshold, the certificate, and the four-month validity remain, but the location and internal references change. Article 7 is not, however, a simple transposition: it also absorbs Article 35, paragraph 6-ter, of Decree-Law No 223 of 2006 in a paragraph 9 dedicated to subcontractors under the reverse charge, and must therefore be read in full, not by difference. On the same date, several other provisions cited here are also repealed, starting with the TUIR: all citations will need to be reviewed together. In contracts currently being drafted, it is advisable to refer to the provision by adding “or any provision that replaces it”.

In practice

It is first worth verifying whether the contract truly falls under Article 17-bis — remembering that the threshold is measured in the upstream relationship, not link by link — and reconstructing the fraction before requesting the certificate, not afterwards, by recovering the items listed above. And if the DURF is requested by contract rather than by law, the clause must be read for what it is: it does not change the scope of the provision, but still binds those who have signed it.

If the certificate is not issued, or arrives with a calculation that does not add up, there is no point in simply resubmitting the application: the Agency points out that a review can be requested from the office that issued it, reporting any data considered not to have been taken into account and using the same application form, approved by the Director’s Provision prot. No 54730 of 6 February 2020. It is advisable to keep the schedule reconstructing the numerator, together with the supporting payment receipts.

Frequently asked questions

Does the DURF also cover social security contributions?

No, and it does not replace the DURC. The certificate attests the requirements of paragraph 5, which include, however, debts for social security contributions assigned to collection agents exceeding 50,000 euro. As for offsetting, a company that communicates to the principal the existence of the requirements by attaching the certification is not subject to the prohibition in paragraph 8, which in any case concerns only statutory contributions and premiums accrued during the contract on the remuneration of personnel directly employed in the works, and not those required by contract such as health funds and supplementary pensions.

What must the principal do, and what are the risks, in the event of irregularity?

The check is carried out at the deadline of paragraph 2, i.e., within five working days after the deadline for paying the withholdings. If, by that date, a certain, liquid, and enforceable consideration has accrued, the principal must suspend payment for as long as the default continues, excluding advances already made. The amount is not at its discretion: if the documentation has not been transmitted, it may retain only 20 per cent of the total value of the work or service; if, on the other hand, it has been received and unpaid withholdings are found, it retains the lesser of that 20 per cent and the unpaid amount. It must then notify the Revenue Agency office having jurisdiction over the principal itself within ninety days of detecting the default, and the contractor or awardee company is precluded from any enforcement action on the suspended credit until the withholdings are paid. If the principal fails to comply with the obligations of paragraphs 1 and 3 — i.e., does not obtain the delegations, or does not suspend payment when it should — it is liable to pay an amount equal to the penalty imposed on the company for the violation of the obligations of correct determination, execution, and timely payment of withholdings, without the possibility of offsetting. However, Circular No 1/E of 2020 limits this in three ways: it is calculated only on the portion of withholdings relating to workers directly employed in the works for that principal; it is due only if those penalties have actually been imposed on the company; and it is not due at all if the company has complied correctly or has remedied the violation through voluntary correction before the violation is formally challenged. However, the latter option is available to the company for its own tax violation, not to the principal for the amount charged to it: the same circular indeed classifies the latter among the non-tax administrative penalties, with the application of Law No 689 of 24 November 1981 and not the principles of Legislative Decree No 472 of 1997.

Does paying a tax collection notice help to reach the 10 per cent?

No. Circular No 1/E of 2020 explicitly excludes from the numerator payments of debts registered for collection. However, after ruling No 63 of 2026, payments made to settle a notice of irregularity before registration for collection are computable: the difference between the two moments affects the calculation.

Sources

Article 17-bis of Legislative Decree No 241 of 9 July 1997, text in force as of 18 September 2026 and version in force from 1 January 2027 (Normattiva, multi-version view).

Article 4 of Decree-Law No 124 of 26 October 2019, converted with amendments by Law No 157 of 19 December 2019.

Revenue Agency, Circular No 1/E of 12 February 2020, paragraphs 2.2, 3.1, 3.2, 4.1, 4.3 and 5.

Revenue Agency, Resolution No 53/E of 22 September 2020.

Revenue Agency, ruling No 63 of 3 March 2026.

Revenue Agency, ruling No 174 of 16 September 2026.

Revenue Agency, Director’s Provision prot. No 54730 of 6 February 2020.

Articles 3(10), 7, 241(1)(t) and 243 of the consolidated text on payments and collection, annexed to Legislative Decree No 33 of 24 March 2025; Article 4, paragraph 4, of Decree-Law No 200 of 31 December 2025, converted by Law No 26 of 27 February 2026.

Articles 23, 26 and 36-bis of Presidential Decree No 600 of 29 September 1973; Article 54-bis of Presidential Decree No 633 of 26 October 1972; Articles 121 and 165 of the TUIR; Article 30 of Legislative Decree No 81 of 15 June 2015; Articles 1322, 1341 and 2222 of the civil code; Article 7 of Legislative Decree No 231 of 9 October 2002; Law No 689 of 24 November 1981 and Legislative Decrees No 471 and No 472 of 18 December 1997; Presidential Decree No 445 of 28 December 2000.